presol_stuffing.c File Reference

Detailed Description

fix singleton continuous variables

Author

Dieter Weninger

Investigate singleton continuous variables if one can be fixed at a bound.

Definition in file presol_stuffing.c.

#include "blockmemshell/memory.h"
#include "scip/presol_stuffing.h"
#include "scip/pub_matrix.h"
#include "scip/pub_message.h"
#include "scip/pub_misc_sort.h"
#include "scip/pub_presol.h"
#include "scip/pub_var.h"
#include "scip/scip_general.h"
#include "scip/scip_mem.h"
#include "scip/scip_message.h"
#include "scip/scip_nlp.h"
#include "scip/scip_numerics.h"
#include "scip/scip_presol.h"
#include "scip/scip_pricer.h"
#include "scip/scip_prob.h"
#include "scip/scip_probing.h"
#include "scip/scip_var.h"
#include <string.h>

Go to the source code of this file.

Macros
#define	PRESOL_NAME   "stuffing"
#define	PRESOL_DESC   "fix redundant singleton continuous variables"
#define	PRESOL_PRIORITY   -100
#define	PRESOL_MAXROUNDS   0
#define	PRESOL_TIMING   SCIP_PRESOLTIMING_EXHAUSTIVE /* timing of the presolver (fast, medium, or exhaustive) */

Typedefs
typedef enum Fixingdirection	FIXINGDIRECTION

Enumerations
enum	Fixingdirection {   FIXATLB = -1 ,   NOFIX = 0 ,   FIXATUB = 1 ,   FIXATLB = -1 ,   NOFIX = 0 ,   FIXATUB = 1 ,   FIXATLB = -1 ,   NOFIX = 0 ,   FIXATUB = 1 ,   FIXATLB = -1 ,   NOFIX = 0 ,   FIXATUB = 1 }

Functions
static SCIP_RETCODE	singletonColumnStuffing (SCIP *scip, SCIP_MATRIX *matrix, FIXINGDIRECTION *varstofix, int *nfixings)
static	SCIP_DECL_PRESOLCOPY (presolCopyStuffing)
static	SCIP_DECL_PRESOLEXEC (presolExecStuffing)
SCIP_RETCODE	SCIPincludePresolStuffing (SCIP *scip)

Macro Definition Documentation

PRESOL_NAME

#define PRESOL_NAME   "stuffing"

Definition at line 57 of file presol_stuffing.c.

PRESOL_DESC

#define PRESOL_DESC   "fix redundant singleton continuous variables"

Definition at line 58 of file presol_stuffing.c.

PRESOL_PRIORITY

#define PRESOL_PRIORITY   -100

priority of the presolver (>= 0: before, < 0: after constraint handlers)

Definition at line 59 of file presol_stuffing.c.

PRESOL_MAXROUNDS

#define PRESOL_MAXROUNDS   0

maximal number of presolving rounds the presolver participates in (-1: no limit)

Definition at line 60 of file presol_stuffing.c.

PRESOL_TIMING

#define PRESOL_TIMING   SCIP_PRESOLTIMING_EXHAUSTIVE /* timing of the presolver (fast, medium, or exhaustive) */

Definition at line 61 of file presol_stuffing.c.

Typedef Documentation

FIXINGDIRECTION

typedef enum Fixingdirection FIXINGDIRECTION

Definition at line 70 of file presol_stuffing.c.

Enumeration Type Documentation

Fixingdirection

enum Fixingdirection

type of fixing direction

Enumerator
FIXATLB	fix variable at lower bound
NOFIX	do not fix variable
FIXATUB	fix variable at upper bound
FIXATLB	fix variable at lower bound
NOFIX	do not fix variable
FIXATUB	fix variable at upper bound
FIXATLB
NOFIX	fix variable at its lower bound
FIXATUB	no fixing
FIXATLB	fix variable at lower bound
NOFIX	do not fix variable
FIXATUB	fix variable at upper bound

Definition at line 64 of file presol_stuffing.c.

Function Documentation

singletonColumnStuffing()

static SCIP_RETCODE singletonColumnStuffing ( SCIP *  scip, SCIP_MATRIX *  matrix, FIXINGDIRECTION *  varstofix, int *  nfixings  )

static

try to fix singleton continuous variables

Parameters

scip	SCIP main data structure
matrix	matrix containing the constraints
varstofix	array holding fixing information
nfixings	number of possible fixings

Definition at line 78 of file presol_stuffing.c.

References BMSclearMemoryArray, FALSE, FIXATLB, FIXATUB, NULL, SCIP_Bool, SCIP_CALL, SCIP_LOCKTYPE_MODEL, SCIP_OKAY, SCIP_Real, SCIPallocBufferArray, SCIPfreeBufferArray, SCIPisGE(), SCIPisGT(), SCIPisInfinity(), SCIPisLE(), SCIPisLT(), SCIPmatrixGetColIdxPtr(), SCIPmatrixGetColNDownlocks(), SCIPmatrixGetColNNonzs(), SCIPmatrixGetColNUplocks(), SCIPmatrixGetNColumns(), SCIPmatrixGetNRows(), SCIPmatrixGetRowIdxPtr(), SCIPmatrixGetRowLhs(), SCIPmatrixGetRowNNonzs(), SCIPmatrixGetRowValPtr(), SCIPmatrixGetVar(), SCIPmatrixIsRowRhsInfinity(), SCIPsortRealRealIntInt(), SCIPvarGetLbGlobal(), SCIPvarGetNLocksDownType(), SCIPvarGetNLocksUpType(), SCIPvarGetObj(), SCIPvarGetUbGlobal(), SCIPvarIsIntegral(), and TRUE.

Referenced by SCIP_DECL_PRESOLEXEC().

SCIP_DECL_PRESOLCOPY()

static SCIP_DECL_PRESOLCOPY ( presolCopyStuffing  )

static

copy method for constraint handler plugins (called when SCIP copies plugins)

Definition at line 346 of file presol_stuffing.c.

References NULL, PRESOL_NAME, SCIP_CALL, SCIP_OKAY, SCIPincludePresolStuffing(), and SCIPpresolGetName().

SCIP_DECL_PRESOLEXEC()

static SCIP_DECL_PRESOLEXEC ( presolExecStuffing  )

static

execution method of presolver

Definition at line 360 of file presol_stuffing.c.

References BMSclearMemoryArray, FALSE, FIXATLB, FIXATUB, NULL, SCIP_Bool, SCIP_CALL, SCIP_CUTOFF, SCIP_DIDNOTFIND, SCIP_DIDNOTRUN, SCIP_LOCKTYPE_MODEL, SCIP_OKAY, SCIP_Real, SCIP_STAGE_PRESOLVING, SCIP_SUCCESS, SCIPallocBufferArray, SCIPallowStrongDualReds(), SCIPdebugMsg, SCIPfixVar(), SCIPfreeBufferArray, SCIPgetNActivePricers(), SCIPgetNContVars(), SCIPgetStage(), SCIPinProbing(), SCIPisInfinity(), SCIPisNLPEnabled(), SCIPisStopped(), SCIPmatrixCreate(), SCIPmatrixFree(), SCIPmatrixGetColNDownlocks(), SCIPmatrixGetColNUplocks(), SCIPmatrixGetNColumns(), SCIPmatrixGetVar(), SCIPvarGetLbGlobal(), SCIPvarGetName(), SCIPvarGetNLocksDownType(), SCIPvarGetNLocksUpType(), SCIPvarGetUbGlobal(), SCIPvarIsIntegral(), and singletonColumnStuffing().